浒苔绿潮暴发对丁字湾毗邻海域大中型浮游动物群落结构的影响

Effects of the occurrence of Green tide(Ulva prolifera) on marco and mesozooplankton community structure in the sea area near Dingzi Bay

为研究浒苔绿潮暴发对大中型浮游动物群落的影响,2018年5-8月在黄海丁字湾(山东省海阳市)绿潮暴发海域进行了4个航次(绿潮发生前期、暴发期、消亡期以及消亡后期)的生态综合调查。结果表明,调查期间共监测到大中型浮游动物9大类群57种。随着绿潮的生消,浮游动物种类数、丰度和多样性指数均呈先升高后降低的变化趋势,暴发期升至最大,消亡后期降至最低。优势种更替率分别为81%、47%、88%,第一优势类群经历了桡足类-浮游幼虫-桡足类的演替过程。当相似性水平为40%时,浮游动物群落结构可分为绿潮发生前期(Ⅰ)、暴发期和消亡期(Ⅱ)以及消亡后期(Ⅲ)三大类群。冗余分析(RDA)显示,DIN对浮游动物类群有负相关影响,pH对浮游动物类群有正相关影响,DIN和pH对桡足类的影响最大;温盐、溶解氧等环境因子对浮游动物群落结构的影响不显著。

To understand the effect of Green tide(Ulva prolifera) on marco and mesozooplankton communities,4 voyages of comprehensive ecological survey were conducted from May to August 2018 in the sea area near Dingzi Bay,the Yellow Sea(Haiyang,Shandong).The result showed that a total of 57 zooplankton species belonged to 9 taxa.During 4 cruises the number of zooplankton species,the abundance and diversity were consistent,showing the change trend of reaching the maximum at the outbreak stage and the lowest at the late extinction stage.The first dominant taxa underwent the succession process of copepods,pelagic larvae and copepods.The replacement rates of dominant species were 81%,47% and 88% respectively during 4 voyages.Three communites were differentiated for the zooplankton by cluster analysis.Community Ⅰ represented the early stage,Community Ⅱ represented the outbreak and extinction stage,and Community Ⅲ represented the late extinction stage.RDA test showed that inorganic nitrogen and pH were respectively negatively and positively correlated with the structure of zooplankton communities,especially for copepods;other environmental parameters such as temperature,salinity,dissolved oxygen and so on had weak impact on zooplankton community.